Field



2 Sheets-Sheet 1.

F. A. CANFIELD.

'ELECTRIC FUSE.

Patented. Nov. 918'75.

Nmeezz.

2 sheet's-sheet z. F. A, CANFELD.

ELECTRIC Patented Nov. 9, 1875.

' X10/om( 'a tightly-fitting tube of rubber, so he a. water-tight jointbetween. it

toenemen A. onnrinnn,

0F DOVER, NEW JERSEY.

Specification forming port of Lettore Potent No. llc'b,22, datedNovember 9, 1875; application filed ingest 9.8, i675.

To all whom it may concern:

Be it known that I, linnnnizroi; A. Glin- FIELD,of Dover, in the countyol: Morris enti State of New Jersey, have invented n new and usefulImprovement in the Protection oi' Electric Exploders for Mines, whichimprovement-is fully-set forth in the following speci 'cation,rcierencebein g had to the e-ceonipenying drawings.

Exploders for mines and suhaq'ueons worn are very liable to ilifiioultyarising from the water necessorilyfound in minet, anni from thecarelessness of miners in exposing these exploders to it, either beforeor after their entrance into the exploding entity., A. 'very sin allamount of water rendere these expiorlers en-. tircly useless, and nsingle drop of witter will sometimes destroy the 'ei'ect o?? connectedseries of blasts-am for instance, 'when several exploders are conneet'edwith one electrical machine, and Situated in dilfierent blasttuhes, ifone o' them fails `to act properly the. bestei'et of the blast willcertainly he lont, and much'diilicnlty may arise.

My invention isdesigned to protect these exploders from the influenceoi.' the waiter, so that they will act equally Well in wzl-te; The usualcopper exploder, oonieinii nate :tt one end, isnsed, .luto this to maltethe surN rounding copper. The Wires cnniying the electricity are pennedthrough the eentml tube, and brought in eontact with the l'nnni* nnte,or they may he allowedV to enter it slightly. I usually place fnlmnate ol" mei curyjn the bottom of the exploder. Fulminato of silver in droppedupon the inlmiimte of mercury, und the Wires placed in in: ition,so'thztt they slightly enter this fnlnlinete of silver. Surrounding thewires .i pin-ee n ping of seine soft elastic materiel, nnoh' es uti-efperch'or india-rubber, no arranged tht it will completely close theentrance io the rub ber tube, so that when the wires in position theentering ping and ite surroumiing india-rubber tube make n watertightjoint and p rotect the fulminete entirely from the surrounding water.

The entering. Wires might both he inolonecl in one covering, enti, ifthis is of such o.. eine its exactlyto it the indio-rubber tnhe, noclosing-plug would he necessary.

This expoder may also he. externally protoe'toii hy mother elastic tube,ne desoribedl in the potent heretofore granted me for protectingexplodcrs.

in the accompanying drawings, Figuren li, 2, 3, and et show the detailsol my apparatus, Fig. l is e general View of the whole, Fig. 2, the'longitntlnal cross section. Figs. 3 end i2 eher.' my apparatus linedwithin and without with the proteetin materiel.. Fig. S is ournes-section of Fig. e on the line fc w. it is alongitndinzilerossi-section, showing the indiztrubher tube, as described in my potentfor exploeive oops.

ln Figo. 3 and 4, afis the metal explotlr. o.

cI in 'the external, ond bis the. internal, ruhber tube; A, Figo, 1 and2, the copper ex? ploder or cap, with its fulmilnate o. B is theWater-proof rubber tube, and C the plug enrrouinling theconducting-wiren el und c2, und.

nerentine the accese 'of witter to the i'nimi I L nuto n2.

teni; tho igulsninete within from explosion by monouso-ion.

.ietoro the wires o1 tud o2 are in ponition n. ping oi rubber or othermotorini serves to close the entra-noe to the tube B.

By moons et my invention the expensive uni complicated .eleotrioztiexplodersA new in use inn-y be dispensed with, and the saine cxpioniereused for firing by electricity, .ne in now used for tiring hy fuse; nudthis ein ploder, moreover, znoy'he, rendermi perfectly Sife from dongenarising from the'prceence of Waiter.

These exploderu might also be advantageously employed in the electrictiring); ol, large ounnon .or flelilpiooos. l

Whatl claim ne my invention, and desire toA seenr'o'by Letters Potent,ism

l. The exploder A, lined with rubber or other similar material,substantially un ile eorihcci.

.out with elastic 2.` The Le'exnbnation af the mb'baz--Einedmetllicfexploder A. with the entering cammen ing-wires e1 am'cz',so'az'mnge as to rendez) it Water-prooi', substantially as described.

, 3. An expmar @uttered within and withmaterial, for the purpose ofrendering it; sauf@ fsmm. xplmaion by cousus;-

l sion, ai; the mme tima pretng from 4 manca of mig ubztantlally as de#fmiued.

FMDK., A.. UANEIELD. "'Vinmamm:

@EN Hammam, JN0. E, hammams.

